
/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_STREAM_UPSTREAM_ROUND_ROBIN_H_INCLUDED_
#define _NGX_STREAM_UPSTREAM_ROUND_ROBIN_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_stream.h>


typedef struct ngx_stream_upstream_rr_peer_s ngx_stream_upstream_rr_peer_t;

struct ngx_stream_upstream_rr_peer_s
{
    struct sockaddr *sockaddr;
    socklen_t        socklen;
    ngx_str_t        name;
    ngx_str_t        server;

    ngx_int_t current_weight;
    ngx_int_t effective_weight;
    ngx_int_t weight;

    ngx_uint_t conns;
    ngx_uint_t max_conns;

    ngx_uint_t fails;
    time_t     accessed;
    time_t     checked;

    ngx_uint_t max_fails;
    time_t     fail_timeout;
    ngx_msec_t slow_start;
    ngx_msec_t start_time;

    ngx_uint_t down;

    void *ssl_session;
    int   ssl_session_len;

#if (NGX_STREAM_UPSTREAM_ZONE)
    ngx_atomic_t lock;
#endif

    ngx_stream_upstream_rr_peer_t *next;

    NGX_COMPAT_BEGIN(25)
    NGX_COMPAT_END
};


typedef struct ngx_stream_upstream_rr_peers_s ngx_stream_upstream_rr_peers_t;

struct ngx_stream_upstream_rr_peers_s
{
    ngx_uint_t number;

#if (NGX_STREAM_UPSTREAM_ZONE)
    ngx_slab_pool_t                *shpool;
    ngx_atomic_t                    rwlock;
    ngx_stream_upstream_rr_peers_t *zone_next;
#endif

    ngx_uint_t total_weight;

    unsigned single   : 1;
    unsigned weighted : 1;

    ngx_str_t *name;

    ngx_stream_upstream_rr_peers_t *next;

    ngx_stream_upstream_rr_peer_t *peer;
};


#if (NGX_STREAM_UPSTREAM_ZONE)

#define ngx_stream_upstream_rr_peers_rlock(peers) \
                                                  \
    if (peers->shpool)                            \
    {                                             \
        ngx_rwlock_rlock(&peers->rwlock);         \
    }

#define ngx_stream_upstream_rr_peers_wlock(peers) \
                                                  \
    if (peers->shpool)                            \
    {                                             \
        ngx_rwlock_wlock(&peers->rwlock);         \
    }

#define ngx_stream_upstream_rr_peers_unlock(peers) \
                                                   \
    if (peers->shpool)                             \
    {                                              \
        ngx_rwlock_unlock(&peers->rwlock);         \
    }


#define ngx_stream_upstream_rr_peer_lock(peers, peer) \
                                                      \
    if (peers->shpool)                                \
    {                                                 \
        ngx_rwlock_wlock(&peer->lock);                \
    }

#define ngx_stream_upstream_rr_peer_unlock(peers, peer) \
                                                        \
    if (peers->shpool)                                  \
    {                                                   \
        ngx_rwlock_unlock(&peer->lock);                 \
    }

#else

#define ngx_stream_upstream_rr_peers_rlock(peers)
#define ngx_stream_upstream_rr_peers_wlock(peers)
#define ngx_stream_upstream_rr_peers_unlock(peers)
#define ngx_stream_upstream_rr_peer_lock(peers, peer)
#define ngx_stream_upstream_rr_peer_unlock(peers, peer)

#endif


typedef struct
{
    ngx_uint_t                      config;
    ngx_stream_upstream_rr_peers_t *peers;
    ngx_stream_upstream_rr_peer_t  *current;
    uintptr_t                      *tried;
    uintptr_t                       data;
} ngx_stream_upstream_rr_peer_data_t;


ngx_int_t
ngx_stream_upstream_init_round_robin(ngx_conf_t                     *cf,
                                     ngx_stream_upstream_srv_conf_t *us);
ngx_int_t
ngx_stream_upstream_init_round_robin_peer(ngx_stream_session_t           *s,
                                          ngx_stream_upstream_srv_conf_t *us);
ngx_int_t
          ngx_stream_upstream_create_round_robin_peer(ngx_stream_session_t           *s,
                                                      ngx_stream_upstream_resolved_t *ur);
ngx_int_t ngx_stream_upstream_get_round_robin_peer(ngx_peer_connection_t *pc,
                                                   void                  *data);
void      ngx_stream_upstream_free_round_robin_peer(ngx_peer_connection_t *pc,
                                                    void *data, ngx_uint_t state);


#endif /* _NGX_STREAM_UPSTREAM_ROUND_ROBIN_H_INCLUDED_ */
